The answer for the question would be D
It's not possible for a number to not have any prime factors be cause the number will always be able to have the factor of 1 whcih is a prime number
Answer: the sample size should be 39
Step-by-step explanation:
The sample mean is the point estimate for the population mean. Confidence interval is written as
Sample mean ± margin of error
Margin of error = z × σ/√n
Where
σ = population standard Deviation
n = number of samples
z represents the z score corresponding to the confidence level
From the information given,
σ = 4 minutes
Margin of error = 75 seconds. Converting to minutes, it becomes 75/60 = 1.25 minutes
To determine the z score, we subtract the confidence level from 100% to get α
α = 1 - 0.95 = 0.05
α/2 = 0.05/2 = 0.025
This is the area in each tail. Since we want the area in the middle, it becomes
1 - 0.025 = 0.975
The z score corresponding to the area on the z table is 1.96. Thus, confidence level of 95% is 1.96
Therefore,
1.25 = 1.96 × 4/√n
1.25/1.96 = 4/√n
0.6378 = 4/√n
√n = 4/0.6378 = 6.27
n = 6.27² = 39
Answer:
x=-3, x=1, x=8
Step-by-step explanation:
When you have to find the zero of an equation like (x+3) all you have to do is solve for x.
x+3=0 equal the equation to zero
x+3-3=0-3 cancel out 3
x=-3 answer
If you have to find the zero of an equation like f(x)=-2x^2 - 5x + 7 then you would have to factor the equation.
7*-2=-14 multiply
-7 & 2 find the two numbers that when multiplied =14 and when added = -5
(2x^2 + 2) (-7x + 7) replace -5 with -7 & 2
-2x (x - 1) -7 (x - 1) factor
(x - 1) (-2x - 7) rewrite
1st: x - 1 = 0
x = 1 : Answer
2nd: -2x - 7= 0
-2x - 7 + 7 = 0 + 7
-2x = 7
-2x / -2 = 7 / -2
x = 7 / -2 : Answer
